Woolly mammoths, woolly rhinos and other large animals driven to extinction since the last ice age each succumbed to a different lethal mix of circumstances...

Researchers who studied the fate of six species of 'megafauna' over the past 50,000 years found that climate change and habitat loss were involved in many of the extinctions, with humans playing a part in some cases but not others. But there was no clear pattern to explain why the animals died off, and it proved impossible to predict from habitat or genetic diversity which species would go extinct and which would survive.

"It almost seems like it's a random process," says Eske Willerslev, a palaeo-geneticist at the University of Copenhagen who led the study published online today in Nature1. "If you ran the whole experiment again, we would have woolly mammoths and no reindeer, so Santa would drag his sleigh with woolly mammoths."

...Some scientists, noting that modern humans were spreading throughout the world around this time, envisaged a blitzkrieg in which technologically savvy people hunted these animals to extinction. The end of an ice age and the habitat changes it wrought led other researchers to lay the blame on climate...

The researchers created a series of snapshots of the European, Asian and North American ranges of these animals (drawn from climate records and hundreds of fossils) and a rough approximation of their population size (based on ancient mitochondrial DNA sequences) between 42,000 and 6,000 thousand years ago...

The team found no way to predict the future extinction of a species, based on either an animal's genetic diversity or the size of its range.

One of my favorite pieces in my knife collection is a Benchmade Gold class folder, with a Damascus blade and a pure white mammoth ivory handle. Hand made, limited edition of 100.

There’s lots of mammoth ivory out there, but most is yellowish, with heavy graining and striping. This stuff is white and smooth. It’s simply breathtaking. And to think how old that ivory is... Staggering.

11
posted on 11/04/2011 7:55:41 PM PDT
by Ramius
(personally, I give us... one chance in three. More tea?)

Researchers who studied the fate of six species of 'megafauna' over the past 50,000 years found that climate change and habitat loss were involved in many of the extinctions, with humans playing a part in some cases but not others.

I was watching a show about this the other day and they were saying that climate change was unlikely to have killed the giant armadillo. It survived for more than a million years through multiple ice ages and the wide climatic swings between the. I turn around the next day and I see a "climatologist" declaring that animals are all going to become extinct because of global warming.

12
posted on 11/04/2011 7:57:15 PM PDT
by cripplecreek
(A vote for Amnesty is a vote for a permanent Democrat majority. ..Choose well.)

I gather that wooly mammoth were also very limited in genetic diversity.

A biological theory, the “island theory”, is that when a species are broken up on different isolated islands, they first diversify and become specialized to their individual islands, eventually becoming unique species, but are condemned to dying out because they become both over-specialized and inbred.

The same basic thing may have happened to wooly mammoths, by distance between herds.

I disagree. I think it is purely the large size. When primitive man invented the bow and arrow, all super sized meat on the hoof became easy pickins. Only in africa and india did supersized meat survive...which makes us wonder what was wrong with the humans in those two locations. In india they learned to tame the supersized animals. But in africa, it seems they just didn’t learn.

There is no clear pattern because the basic premise is wrong. When you figure out the question, then the pattern emerges. But if by pre-determination you have eliminated some questions, I would start there where there is no pattern.

Clues, Polar ice is thickest at the magnetic poles rather than the solar poles...

What causes water to react to magnetic fields...

How did Woolly mammoths die with flowers preserved in their stomachs... How, without digesting? Did the earths magnetic poles ever reverse... How, what could cause that?... Connect the dots.

19
posted on 11/04/2011 8:23:16 PM PDT
by American in Israel
(A wise man's heart directs him to the right, but the foolish mans heart directs him toward the left.)

Try the flooding of Lake Missoula and creation of the Columbia Gorge as one reason the Columbia wooly mamoth may have been wiped out. That was one epic (actually several) flood. Sixty MPH, and 200+ feet above current river levels. Boulders so large they were carried to the Oregon Coast Range.

I wouldn’t be surprised. There’s an astonishing amount of mammoth ivory raw material available. Especially now that other forms of ivory are largely illegal, and mammoth tusks keep being found all over the artic in the U.S., Canada and Russia... It may not be exactly plentiful, but it is available. If you want a set of mammoth ivory grips for your Colt 1911... They can be found without much trouble.

The big difference is the quality of the ivory. Most of the mammoth ivory is yellowed, or has harsh grain, stains, and lots of marking in it. Dark stripes from cracks are common. What attracted me to the knife was the pure white ivory. In mammoth ivory I’ve seen, that’s fairly uncommon. That tells me they had a pretty special sample from which to make their handles.

23
posted on 11/04/2011 9:42:49 PM PDT
by Ramius
(personally, I give us... one chance in three. More tea?)

Are you talking about the flood from the break of the ice dam? If you’ve ever been to “dry falls” in WA, they figure that the canyon downstream of dry falls was formed all at once... Maybe a period of three or so DAYS, after the ice dam finally broke.

Amazing stuff.

24
posted on 11/04/2011 9:49:32 PM PDT
by Ramius
(personally, I give us... one chance in three. More tea?)

There are two theoretical possibilities for flash freezing 6-10 ton beasties:

Velokovski's close approach of the protoplanet Venus (He correctly predicted both the temperature and composition of Venus’ atmosphere before any probes were sent. The prevailing view at that time was that Venus was a warmer version of Earth).

and;

The Northern Ice Cap had massive freshwater lakes - think the Great Lakes super sized - which collapsed into the warmer oceans sending water vapor into the stratosphere, which then fell back to Earth supercooled, flash freezing the beasts.

Theories abound, but none can be verified, currently.

27
posted on 11/05/2011 6:13:00 AM PDT
by PIF
(They came for me and mine ... now it is your turn ...)

High in the north above Siberia, six hundred miles inside the Polar Circle, in the Arctic Ocean, lie the Liakhov Islands. Liakhov was a hunter who, in the days of Catherine II, ventured to these islands and brought back the report that they abounded in mammoths’ bones. “Such was the enormous quantity of mammoths’ remains that it seemed . . . that the island was actually composed of the bones and tusks of elephants, cemented together by icy sand.” 3

The New Siberian Islands, discovered in 1805 and 1806, as well as the islands of Stolbovoi and Belkov to the west, present the same picture. “The soil of these desolate islands is absolutely packed full of the bones of elephants and rhinoceroses in astonishing numbers.” 4

30
posted on 11/05/2011 6:24:25 AM PDT
by SunkenCiv
(It's never a bad time to FReep this link -- https://secure.freerepublic.com/donate/)

That’s a nice story, but there’s no discernable evidence of a disease in the last mammoths. There is however evidence for sudden extinction. Yes, there were some isolated populations (dwarfed) which persisted until perhaps 2000 years ago, and the Earth can only show one face to the incoming space crud which was found embedded in the tusks of the last North American mammoths. :’)

37
posted on 11/05/2011 5:25:34 PM PDT
by SunkenCiv
(It's never a bad time to FReep this link -- https://secure.freerepublic.com/donate/)

My folks just gave my son a book called "Dinosaurs for Kids," a creationist theory about how dinosaurs lived and eventually died out. My boy is five and I don't want to have to explain to him the mental gymnastics this author has to do to come up with his theories. There is even a picture of Adam and Eve in the Garden of Eden with an apple and surrounded by dinosaurs.

This is Robert Bakker’s theory in his 1985 book “The Dinosaur Heresies”. Bakker notes that the mass extinctions at the end of the Cretaceous period did not occur at once but over a period of several million years.

Bakker speculated that because of continental drift historically isolated populations came into contact and thus succumbed to new diseases.

It’s not surprising that the climate change doomsayers borrowed his theory.

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